US6540221B2 - Feeder of an image forming apparatus - Google Patents

Feeder of an image forming apparatus Download PDF

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Publication number
US6540221B2
US6540221B2 US09/929,314 US92931401A US6540221B2 US 6540221 B2 US6540221 B2 US 6540221B2 US 92931401 A US92931401 A US 92931401A US 6540221 B2 US6540221 B2 US 6540221B2
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US
United States
Prior art keywords
feeding roller
separating pad
sheets
separating
feeding
Prior art date
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Expired - Lifetime
Application number
US09/929,314
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English (en)
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US20020060394A1 (en
Inventor
Akira Nakashima
Takashi Kubo
Yasumasa Morimoto
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Sharp Corp
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Sharp Corp
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Assigned to SHARP KABUSHIKI KAISHA reassignment SHARP KABUSHIKI KAISHA ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KUBO, TAKASHI, MORIMOTO, YASUMASA, NAKASHIMA, AKIRA
Publication of US20020060394A1 publication Critical patent/US20020060394A1/en
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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H3/00—Separating articles from piles
    • B65H3/46—Supplementary devices or measures to assist separation or prevent double feed
    • B65H3/52—Friction retainers acting on under or rear side of article being separated
    • B65H3/5207—Non-driven retainers, e.g. movable retainers being moved by the motion of the article
    • B65H3/5215—Non-driven retainers, e.g. movable retainers being moved by the motion of the article the retainers positioned under articles separated from the top of the pile
    • B65H3/5223—Retainers of the pad-type, e.g. friction pads
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2301/00—Handling processes for sheets or webs
    • B65H2301/40—Type of handling process
    • B65H2301/42—Piling, depiling, handling piles
    • B65H2301/423—Depiling; Separating articles from a pile
    • B65H2301/4232—Depiling; Separating articles from a pile of horizontal or inclined articles, i.e. wherein articles support fully or in part the mass of other articles in the piles
    • B65H2301/42324—Depiling; Separating articles from a pile of horizontal or inclined articles, i.e. wherein articles support fully or in part the mass of other articles in the piles from top of the pile
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2402/00—Constructional details of the handling apparatus
    • B65H2402/30—Supports; Subassemblies; Mountings thereof
    • B65H2402/31—Pivoting support means
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2402/00—Constructional details of the handling apparatus
    • B65H2402/30—Supports; Subassemblies; Mountings thereof
    • B65H2402/32—Sliding support means
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2402/00—Constructional details of the handling apparatus
    • B65H2402/50—Machine elements
    • B65H2402/54—Springs, e.g. helical or leaf springs
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2405/00—Parts for holding the handled material
    • B65H2405/10—Cassettes, holders, bins, decks, trays, supports or magazines for sheets stacked substantially horizontally
    • B65H2405/11—Parts and details thereof
    • B65H2405/111—Bottom
    • B65H2405/1117—Bottom pivotable, e.g. around an axis perpendicular to transport direction, e.g. arranged at rear side of sheet support

Definitions

  • the present invention is applied to image forming apparatuses such as a printer, a copy machine, and a facsimile which form images on sheets by such processes as printing and transfer, and more specifically relates to a feeder which separates stacked sheets into individual sheets in order and carries sheets to an image forming section.
  • a fixing type feeding cassette which utilizes a bottom plate of the image forming apparatus body as a bottom plate of the feeding cassette tends to be installed instead of the detachable feeding cassette.
  • the fixing type can store fewer sheets, but the fixing type has an advantage that the height of the image forming apparatus can be decreased.
  • the fixing type feeding cassette because it is fixed, problems which did not occur in the detachable type are brought about. That is, unlike the detachable type feeding cassettes which can classify sheets according to size and type of the sheets to some extent by the feeding cassette and can fix feeding conditions in a predetermined range, the fixing type feeding cassette need to solely cope with various sheets which differ in size, thickness, and surface smoothness, etc. Thus, feeding conditions need to be fixed with respect to every kind of sheet used in the feeder.
  • the feeding conditions include a sheet transport power for feeding and transport sheets out of the feeding cassette, and sheet separating power for separating the sheets into individual sheets.
  • FIG. 7 An arrangement of a conventional feeder using the fixing type feeding cassette is shown in FIG. 7 .
  • a bottom plate of a fixing type feeding cassette 50 makes up a bottom 57 of an image forming apparatus body, and a sheet lifting plate 59 which pushes up an end of stacked sheets S stored in the feeding cassette 50 is provided on the bottom plate 57 .
  • the sheet lifting plate 59 rises by switching off a solenoid 58 , so that a front end of the sheets S stacked on the sheet lifting plate 59 is pushed against a feeding roller 51 .
  • the feeding roller 51 is provided along a body frame 54 , which is also a right side wall of the image forming apparatus, and a roller section of the feeding roller 51 is divided into plural rollers and provided on a shaft 51 a which stretches from the front side to the rear side (see FIG. 4, an explanatory drawing of the present invention in which the feeding roller is indicated by reference number 5 and the roller section is divided into four rollers in FIG. 4 ).
  • a sheet separating section for preventing transport of plural sheets S is provided below the feeding roller 51 , downstream with respect to a position where a front end of the sheets S is pressed against.
  • the sheet separating section is made up of a separating unit 52 which is provided for each of the divided rollers of the feeding roller 51 .
  • the separating unit 52 includes a separating pad 55 thereon, and the separating pad 55 is pressed against the feeding roller 51 .
  • the separating unit 52 is fixed on the body frame 54 via a mounting fraction 52 a with a bolt 60 , and pushed along a guide rib 53 provided straight up on the bottom plate 57 of the image forming apparatus in a direction shown by an arrow e by a spring 56 whose end is fixed on the bottom plate 57 .
  • the separating pad 55 above the spring 56 is pressed against the feeding roller 51 by the pushing force of the spring 56 .
  • the guide rib 53 restricts a direction of pressure in pressing the separating pad 55 against the feeding roller 51 .
  • the sheet lifting plate 59 rises by switching off the solenoid 58 and a front end of the sheets S is pressed against the feeding roller 51 , so that the sheets S in the feeding cassette 50 are pulled out by rotation of the feeding roller 51 and carried between the feeding roller 51 and the separating pad 55 .
  • the plural sheets S are pulled out together one over another, the plural sheets cannot pass between the feeding roller 51 and the separating pad 55 pressed against the feeding roller 51 , and the sheets are separated into individual sheets to prevent transport of plural sheets.
  • a sheet S having passed through between the feeding roller 51 and the separating pads 55 is carried to an image forming section (not shown) in accordance with the rotation of the feeding roller 51 .
  • the first object of the present invention is to provide a feeder of an image forming apparatus which can feed sheets stably over extended periods of time by improving durability of a separating pad.
  • the second object of the present invention is to provide a feeder of an image forming apparatus which is suitable for a feeder having a fixing type feeding cassette and can prevent transport of plural sheets without fail and without impairing sheets carrying performance regardless of type, size, and surface smoothness etc. of fed sheets.
  • a feeder of an image forming apparatus of the present invention to achieve the first object, pressure switching means for pressing a separating pad against a feeding roller only when feeding sheets, wherein, when feeding sheets, said pressure switching means presses the separating pad against the feeding roller, and the feeding roller is rotated, so as to separate stacked sheets into individual sheets between the feeding roller and the separating pad and carry the sheets individually to an image forming section.
  • the pressure switching means presses the separating pad against the feeding roller only when feeding sheets, a pressed surface of the separating pad is hard to wear out, compared with a conventional arrangement in which the separating pad was pressed all the time.
  • durability of the separating pad can be improved.
  • stable sheet feeding can be maintained over extended periods of time.
  • a feeder of an image forming apparatus includes separating pad displacing means for displacing a separating pad in a direction away from a feeding roller according to a thickness of a sheet passing through between the separating pad and the feeding roller, wherein, only when feeding sheets, said separating pad is pressed against said feeding roller, and the feeding roller is rotated, so as to separate stacked sheets into individual sheets between the feeding roller and the separating pad and carry the sheets individually to an image forming section.
  • the separating pad displacing means displaces the separating pad in a direction away from the feeding roller according to a thickness of a sheet passing through between the separating pad and the feeding roller, an unnecessary increase of pressure brought about by differences in thickness of sheets can be avoided appropriately, in comparison with a conventional arrangement in which the separating pad was hardly displaced.
  • the pressure of the separating pad can be made in accordance with a thickness of a sheet passing through between the separating pad and the feeding roller.
  • various sheets can be used to separate sheets into individual sheets without fail and without impairing sheet carrying performance, and transport of plural sheets can be prevented.
  • the foregoing arrangement is particularly effective when applied to a feeder having a fixing type feeding cassette which cannot adjust separating pressure according to type or size of sheets and need to separate various sheets appropriately.
  • a feeder of an image forming apparatus of the present invention to achieve the first and the second objects includes, a rotatable pressing support base for pressing a separating pad against a feeding roller and for rotating the separating pad so that the separating pad is displaced in a direction away from the feeding roller in accordance with a thickness of a sheet passing through between the separating pad and the feeding roller; and support base moving means for moving the rotatable pressing support base between a standby position where the separating pad is separated from the feeding roller and a pressing position where the separating pad is pressed against the feeding roller, wherein, when feeding sheets, the separating pad is pressed against the feeding roller, and the feeding roller is rotated, so as to separate stacked sheets and carry the sheets individually to an image forming section.
  • the rotatable pressing support base presses the separating pad against the feeding roller and rotates the separating pad in a direction away from the feeding roller according to a thickness of a sheet passing through between the separating pad and the feeding roller, an unnecessary increase of pressure brought about by differences in thickness of sheets can be avoided appropriately, in comparison with a conventional arrangement in which the separating pad was hardly displaced.
  • the pressure of the separating pad can be made in accordance with a thickness of a sheet passing through between the separating pad and the feeding roller.
  • various sheets can be used to separate sheets into individual sheets without fail without impairing sheet carrying performance, and transport of plural sheets can be prevented.
  • the foregoing arrangement is particularly effective when applied to a feeder having a fixing type feeding cassette which cannot adjust separating pressure according to type or size of sheets and need to separate various sheets appropriately.
  • the holder moving means moves the rotatable pressing support base between a standby position where the separating pad is separated from the feeding roller and a pressing position where the separating pad is pressed against the feeding roller, the separating pad can be pressed against the feeding roller only when feeding sheets. Therefore, a pressed surface of the separating pad is hard to wear out, compared with a conventional arrangement in which the separating pad was pressed all the time. Thus, durability of the separating pad can be improved. As a result, stable feeding can be maintained over extended periods of time.
  • FIG. 1 ( a ) is a cross sectional view showing a state of a feeder installed in an ink-jet printer as an image forming apparatus according to an embodiment of the present invention when feeding sheets
  • FIG. 1 ( b ) is a cross sectional view showing a state of the feeder in a non-feeding state.
  • FIG. 2 is a perspective view showing an external appearance of the ink-jet printer.
  • FIG. 3 is a cross sectional view showing an arrangement of the ink-jet printer.
  • FIG. 4 is a plan view showing an arrangement in the vicinity of feeding rollers installed in a feeder of the ink-jet printer.
  • FIG. 5 is a cross sectional view showing an arrangement of another feeder installed in the ink-jet printer.
  • FIG. 6 is a cross sectional view showing an arrangement of still another feeder installed in the ink-jet printer.
  • FIG. 7 is a cross sectional view showing an arrangement of a conventional feeder of an image forming apparatus.
  • FIGS. 1 ( a ) and 1 ( b ) through FIG. 6 The embodiment according to the present invention is described based on FIGS. 1 ( a ) and 1 ( b ) through FIG. 6 as follows.
  • FIG. 2 is an external view of the ink-jet printer as viewed from the front left side.
  • FIG. 3 is a longitudinal cross sectional view showing a schematic arrangement of the ink-jet printer 1 .
  • FIG. 4 is a plan view showing an arrangement of a periphery of a feeding roller 5 which makes up a feeding device in the ink-jet printer 1 .
  • the ink-jet printer 1 has a feeding cassette 2 which stores stacked sheets S on a bottom of the ink-jet printer 1 .
  • the feeding cassette is not detachable, but of a fixing type, and a bottom plate 1 a of the ink-jet printer 1 makes up a bottom of the cassette.
  • the bottom plate 1 a of the ink-jet printer 1 has a sheet lifting plate (sheet lifting means) 3 for lifting the sheets S stored in the feeding cassette 2 , and the sheets S stored in the feeding cassette 2 are stacked on the sheet lifting plate 3 .
  • the bottom plate 1 a of the ink-jet printer making up the feeding cassette 2 has sheet inserting guides 16 and 17 (see FIG. 4) on the rear side and the front side, respectively, and a sheet inserting guide 18 (see FIG. 3) is provided at a predetermined distance from the bottom plate 1 a.
  • the sheet inserting guides 16 to 18 Guided by the sheet inserting guides 16 to 18 , the sheets S are inserted from the left side plane of the ink-jet printer 1 into the feeding cassette 2 .
  • the sheet inserting guide 17 provided on the front side is movable back and forth in directions of an arrow a in FIG. 4, and aligns the sheets S stored in the feeding cassette 2 in a rear-front direction.
  • the feeding cassette 2 is also provided with an aligning plate for aligning the stored sheets S in an insertion direction of the sheets S (same as feeding direction).
  • a solenoid 4 which is switched off to lift the sheet lifting plate 3 about a shaft 3 a serving as a fulcrum when the ink-jet printer 1 is requested to print.
  • the solenoid 4 is provided one each for the rear side and the front side of the sheet lifting plate 3 .
  • the sheet lifting plate 3 is lifted so that a leading end of the upper most sheet S of the stacked sheets S is pressed against the feeding roller 5 provided above the sheet lifting plate 3 .
  • the feeding roller 5 against which the sheet S is pressed rotates in a direction shown by an arrow b in FIG. 3 and FIG. 4, and the force of rotation pulls the upper most sheet S of the stacked sheets S stored in the feeding cassette 2 , and carries the pulled sheet S to a recording section (an image forming section) which is provided above the feeding cassette 2 and is described below.
  • the feeding roller 5 has a roller part which is divided and provided on a shaft 6 which is provided along a body frame 1 b which also makes up a right side wall of the ink-jet printer 1 and transmits the driving force of a motor 15 .
  • the roller part is divided into four parts.
  • a sheet separating section 7 for preventing transport of plural sheets S pulled out of the feeding cassette 2 .
  • the sheet separating section 7 is provided for each of the divided four rollers of the feeding roller 5 provided on the shaft 6 . This is described more concretely later.
  • a carrying roller 8 which helps the feeding roller 5 to carry the sheet S and a PS roller (a paper stop roller) 9 which adjusts a leading end of an image.
  • the PS roller 9 matches a leading end of the sheet S with a leading end of the image in position.
  • the PS roller 9 as well as the feeding roller 5 stops rotating temporarily, and rotates again at such a timing that the leading end of the sheet S and the leading end of the image are matched in position, so that the sheet S is carried to the recording section.
  • the recording section includes a recording device 10 and a drying device 12 in order.
  • the recording device 10 is made up of an ink head 10 a which sprays a needed ink corresponding to image data and prints an image on the sheet S, an ink carriage 10 b for installing the ink head 10 a therein, and an ink carriage holding shaft 10 c which is provided to make the scanning smooth.
  • the sheet S is stopped temporarily, and at the time when the ink carriage 10 b completes scanning of one line (one direction) in a main scanning direction, the sheet S is carried by a distance which corresponds to a length in a sub scanning direction of an area where plural ink nozzles of the ink head 10 a are formed. Such processes corresponding to the image data are performed all the time, so that an image is formed on the sheet S with an ink.
  • the printed sheet S is carried to the drying device 12 by a pair of carrying rollers 11 .
  • the drying device 12 dries the ink on the sheet S by spraying air on the sheet S. After dried, the sheet S is discharged to a discharge tray 14 by a pair of discharging rollers 13 .
  • the members indicated by reference numeral 19 in FIG. 3, which were not described particular, are carrying guides for guiding the sheet S which is fed from the feeding cassette 2 and is discharged to the discharging tray 4 .
  • FIG. 1 ( a ) and FIG. 1 ( b ) are longitudinal cross sections showing arrangements of the sheet separating section 7 making up the feeder and its periphery.
  • FIG. 1 ( a ) shows a state of the ink-jet printer 1 feeding sheets
  • FIG. 1 ( b ) shows a non-feeding state, that is, a standby state of the ink-jet printer 1 .
  • the sheet separating section 7 is made up of a movable sheets separating unit (support base moving means) 21 with its upper surface provided with the separating pad 20 which is pressed against the feeding roller 5 .
  • the movable sheet separating unit 21 can move between a pressing position shown in FIG. 1 ( a ) in which the separating pad 20 is pressed against the feeding roller 5 , and a standby position shown in FIG. 1 ( b ) in which the separating pad 20 is separated from the feeding roller 5 , so that the movable sheet separating unit 21 is held in a pressing position only when feeding sheets to press the separating pad 20 against the feeding roller 5 . Since the separating pad 20 is not pressed against the feeding roller 5 all the time but pressed only when feeding sheets, wear of the separating pad 20 is suppressed. Thus, durability of the separating pad 20 can be improved and stable sheet feeding can be realized over extended periods of time.
  • the movable sheet separating unit 21 chiefly includes a base 21 a which also makes up a unit body, a rotatable support base 21 b which is provided on the base 21 a and rotatably supports the separating pad 20 on a fulcrum Z, a pressing spring (a first pushing member) 21 d for pressing the separating pad 20 supported by the rotatable support base 21 b against the feeding roller 5 , and a stopper (position restricting means) 21 c which is stopped on a body frame 1 b so as to restrict height of the movable sheet separating unit 21 by a lifting spring (a second pushing member) 22 .
  • the base 21 a is provided with an operation tongue 21 e by which the height of the movable sheet separating unit 21 can be switched in an interlocking action with the up-down movement of the lifting plate 3 described above.
  • the base 21 a is pushed by the lifting spring 22 whose end is fixed on the bottom plate la of the ink-jet printer 1 , so that the movable sheet separating unit 21 is always pushed up toward the feeding roller 5 .
  • the ink-jet printer 1 is in a non-feeding state, that is, a standby state, as shown in FIG. 1 ( b )
  • the sheet lifting plate 3 is brought into contact with the operation tongue 21 e provided on the base 21 a, so that the operation tongue 21 e is kept pushed downward and cannot move upward.
  • the separating pad 20 can be maintained separated from the feeding roller 5 .
  • the separating pad 20 supported by the rotatable support base 21 b is pressed against the feeding roller 5 by the pushing force of the pressing spring 21 d which pushes the separating pad 20 via the rotatable support base 21 b in a direction of the normal line.
  • the separating pad 20 is pressed against the feeding roller 5 in a direction in which the pushing force of the pressing spring 21 d acts, and pressing is performed at a predetermined pressure needed to separate sheets.
  • the stopper 21 c is provided so that the pushing force of the lifting spring 22 does not directly influence the pressure of the separating pad 20 against the feeding roller 5 .
  • only the pushing force of the pressing spring 21 d is needed to effect control, and it becomes easier to set the pressure.
  • the separating pad is not designed to displace its position away from the feeding roller even when a force acts on the separating pad to spread a spacing between the separating pad and the feeding roller.
  • the plural sheets S are pressed against the feeding roller harder than needed.
  • the sheets S are thick papers such as post cards, there were cases where ends of the sheets S are rolled up or splinter.
  • the separating pad 20 rotates in a direction shown by an arrow c in FIG. 1 ( a ) and is displaced away from the feeding roller 5 so that the spacing between the separating pad 20 and the feeding roller 5 is spread.
  • the plural sheets S are not pressed against the feeding roller 5 harder than needed.
  • the pushing direction of the pressing spring 21 d for pressing the separating pad 20 against the feeding roller 5 coincides with the direction of pressing down the separating pad 20 .
  • the pressing spring 21 d for pressing the separating pad 20 against the feeding roller 5 and the lifting spring 22 for lifting the movable sheets separating unit 21 from the standby position to the pressing position in terms of deformation brought about by loads
  • the pressing spring 21 d is set to be more easily deformed than the lifting spring 22 .
  • the pressing spring 21 d can absorb force which is brought about by a thickness of the sheets S inserted between the separating pad 20 and the feeding roller 5 and exerted on the separating pad 20 appropriately, while the movable sheets separating unit 21 is kept in the pressing position, thereby separating the sheets S efficiently.
  • the position of the movable sheets separating unit 21 is switched in an interlocking action with the movement of the sheet lifting plate 3 for lifting the sheets S when feeding sheets. Therefore, a switching operation by which the separating pad 20 is pressed against the feeding roller 5 only when feeding sheets can be realized easily without increasing the number of members.
  • a single spring 31 is used instead of the two springs of the movable sheets separating unit 21 shown in FIG. 1 ( a ) and FIG. 1 ( b ), that is, the pressing spring 21 d for pressing the separating pad 20 against the feeding roller 5 and the lifting spring 22 for lifting the movable sheets separating unit 21 from the standby position to the pressing position, so that a movable sheets separating unit 30 making up the sheet separating section 7 shown in FIG. 5 is made compact.
  • a rotatable support base 30 b rotatably supporting the separating pad 20 is pushed, together with a unit body 30 a on which the rotatable support base 30 b is fastened, by a spring 31 whose end is fixed on the bottom plate 1 a of the ink-jet printer 1 , and the separating pad 20 is pressed against the feeding roller 5 with a predetermined pressure which acts on the separating pad 20 on an angle, as in the movable sheets separating unit 21 of FIG. 1 ( a ).
  • a stopper 30 c which restricts height of the movable sheet separating unit 30 at the pressing position against the pushing force and prevents the separating pad 20 from being pressed harder than needed against the feeding roller 5 functions as in the movable sheets separating unit 21 . Further, switching between the pressing position and the standby position of the movable sheet separating unit 30 is made with an operation tongue 30 e which is provided on the unit body 30 a, in an interlocking action with up-down movement of the sheet lifting plate 3 as in the movable sheets separating unit 21 .
  • the movable sheets separating unit 33 making up the sheet separating section 7 shown in FIG. 6 has an arrangement in which a single spring 34 is used instead of the two springs in the movable sheets separating unit 21 shown in FIG. 1 ( a ) and FIG.
  • a guide rib 35 which is provided on the side wall of the body of the ink-jet printer 1 for restricting a moving direction of the movable sheets separating unit 33 , is tilted along a direction of a normal line of the separating pad 20 .
  • the spring 34 whose end is fixed on the side wall is pushed in a direction of a normal line of the separating pad 20 so that the separating pad 20 is more easily displaced according to a thickness of the sheets S.
  • a stopper 33 c which restricts height of the movable sheets separating unit 33 at the pressing position against the pushing force of the spring 34 and prevents the separating pad 20 from being pressed harder than needed against the feeding roller 5 functions as in the movable sheets separating unit 21 .
  • an operation tongue 33 e which is provided on the unit body 33 a, switching between the pressing position and the standby position is made in an interlocking action with the up-down movement of the sheet lifting plate 3 as in the movable sheets separating unit 21 .
  • the guide rib for restricting the direction of movement is also provided for the two movable sheets separating units 21 and 30 .
  • a feeder of an image forming apparatus of the present invention in which a separating pad is pressed against a feeding roller, and the feeding roller rotates is rotated, so as to separate stacked sheets into individual sheets between the feeding roller and the separating pad and carry the sheets individually to an image forming section, includes pressure switching means for pressing the separating pad against the feeding roller only when feeding sheets.
  • the separating pad is pressed against the feeding roller only when feeding sheets by the pressure switching means, the surface of the separating pad pressed against the feeding roller is hard to wear and durability of the separating pad can be improved compared with a conventional arrangement in which the separating pad is pressed against the feeding roller all the time. As a result, stable feeding can be maintained over extended periods of time.
  • the feeder of the image forming apparatus may also have an arrangement including sheet lifting means for lifting a front end of the stacked sheets to bring it into contact with the feeding roller when feeding sheets, wherein said pressure switching means presses the separating pad against the feeding roller in an interlocking action with the lifting operation of the sheet lifting means.
  • Another feeder of the image forming apparatus in which, the separating pad is pressed against said feeding roller, and the feeding roller is rotated, so as to separate stacked sheets into individual sheets between the feeding roller and the separating pad and carry the sheets individually to an image forming section, includes separating pad displacing means for displacing a separating pad in a direction away from a feeding roller according to a thickness of a sheet passing through between the separating pad and the feeding roller.
  • pad displacing means displaces the separating pad in a direction away from the feeding roller according to a thickness of a sheet passing through between the separating pad and the feeding roller.
  • this can provide a feeder suitable for a fixing type feeding cassette which cannot adjust separating pressure according to type and size of sheets and needs to separate various sheets properly.
  • said separating pad displacing means includes a first pushing member for pressing the separating pad against the feeding roller, and a pushing force of the first pushing member is set so that the separating pad is displaceable in a direction away from the feeding roller according to a thickness of the sheet passing between the separating pad and the feeding roller.
  • the separating pad displacing means is made up of the first pushing member for pressing the separating pad against the feeding roller
  • said separating pad has a rotating fulcrum so that the separating pad is displaced by rotation in a direction away from the feeding roller against the pushing force of the first pushing member according to a thickness of the sheet passing between the separating pad and the feeding roller.
  • the separating pad since the separating pad is separated from the feeding roller in accordance with the rotation movement using an end of the separating pad as a fulcrum, the separating pad rotates according to changes of thickness of the sheets without the pushing force of the first pushing member as in the arrangement in which the separating pad is displaced in parallel with respect to the feeding roller, so that sheet carrying performance can be improved and transport of plural sheets can be prevented, in addition to improving, durability of the separating pad.
  • Still another feeder of the image forming apparatus of the present invention in which the separating pad is pressed against the feeding roller, and the feeding roller is rotated, so as to separate stacked sheets and carry the sheets individually to an image forming section, includes a rotatable pressing support base for pressing a separating pad against a feeding roller and for rotating the separating pad so that the separating pad is displaced in a direction away from the feeding roller in accordance with a thickness of a sheet passing through between the separating pad and the feeding roller; and support base moving means for moving the rotatable pressing support base between a standby position where the separating pad is separated from the feeding roller and a pressing position where the separating pad is pressed against the feeding roller.
  • the rotatable pressing support base presses the separating pad against the feeding roller and rotates the separating pad in a direction away from the feeding roller according to a thickness of a sheet passing through between the separating pad and the feeding roller, an unnecessary increase of pressure brought about by differences in thickness of sheets can be avoided appropriately, compared with a conventional arrangement in which the separating pad was hardly displaced.
  • the pressure of the separating pad can be made in accordance with a thickness of a sheet passing through between the separating pad and the feeding roller.
  • the support base moving means moves the rotatable pressing support base between the standby position where the separating pad is separated from the feeding roller and the pressing position where the separating pad is pressed against the feeding roller, the separating pad can be pressed against the feeding roller only when feeding sheets.
  • the pressed surface of the separating pad is hard to wear, compared with a conventional arrangement in which the separating pad was pressed all the time. Therefore, durability of the separating pad can be improved. As a result, stable feeding can be maintained over extended periods of time.
  • the feeder of the image forming apparatus may have an arrangement in which said support base moving means includes a second pushing member for lifting the rotatable pressing support base toward the feeding roller so as to press the separating pad against the feeding roller, and a position restricting member which is stopped on a frame of an image forming apparatus body so as to restrict a position of the rotatable pressing support base lifted by the second pushing member to the pressing position.
  • the rotatable pressing support base is lifted by the second pushing member which is provided on the support base moving means so that the separating pad supported by pressure on the rotatable pressing support base is pressed against the feeding roller.
  • the position restricting member is stopped on the frame of the image forming apparatus body to restrict a position of the rotatable pressing support base lifted by the second pushing member to the pressing position.
  • the separating pad is pressed against the feeding roller by the pressure force of the rotatable pressing support base, and unnecessary pushing force of the second pushing member which lifts the rotatable pressing holder is not applied to the separating pad so as not to impede the displacement of the separating pad.
  • the feeder of the image forming apparatus can function appropriately based on the foregoing arrangement.
  • the feeder of the image forming apparatus may have an arrangement including sheet lifting means for lifting a front end of the stacked sheets to bring it into contact with the feeding roller when feeding sheets, wherein said support base moving means moves the rotatable pressing support base to the pressing position in an interlocking action with the lifting operation of the sheet lifting means.
  • the switching operation for displacing the rotatable pressing support base (standby position/pressing position) is performed in an interlocking action with the lifting movement of the sheet lifting means for lifting a front end of the stacked sheets, it is not required to provide an additional member for moving the rotatable pressing support base to the pressing position and pressing the separating pad against the feeding roller only when feeding sheets. Thus, it is easy to perform the switching operation for pressing the separating pad against the feeding roller only when feeding sheets.
US09/929,314 2000-08-29 2001-08-14 Feeder of an image forming apparatus Expired - Lifetime US6540221B2 (en)

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Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020036377A1 (en) * 2000-08-08 2002-03-28 Ricoh Company, Ltd. Method and apparatus for image forming and effectively performing sheet feeding
US20030155702A1 (en) * 2002-02-08 2003-08-21 Toshifumi Togashi Method and apparatus for sheet feeding and image forming apparatus incorporating the same
US6616138B2 (en) * 2000-09-01 2003-09-09 Sharp Kabushiki Kaisha Recording device and a device for separating and feeding paper
US20030179360A1 (en) * 2002-03-20 2003-09-25 Oki Data Corporation Sheet feeding mechanism and image forming apparatus
US20040201163A1 (en) * 2003-04-11 2004-10-14 Brock Kelly A. Media positioning at a picking location
US20040251602A1 (en) * 2003-06-16 2004-12-16 Tom Ruhe Sheet media input structure
US20060082043A1 (en) * 2004-10-14 2006-04-20 Brother Kogyo Kabushiki Kaisha Paper feed unit, paper separating unit, and image forming apparatus
US20060170147A1 (en) * 2005-02-03 2006-08-03 Canon Kabushiki Kaisha Sheet Feeding Apparatus, Image Reading Apparatus, and Image Forming Apparatus
US20080093792A1 (en) * 2006-10-20 2008-04-24 Samsung Electronics Co., Ltd Sheet feeding unit and image forming apparatus having the same
US20080099976A1 (en) * 2004-08-24 2008-05-01 Seiko Epson Corporation Paper Feeding Method and Paper Feeder
US20080315497A1 (en) * 2007-06-20 2008-12-25 Seiko Epson Corporation Feeding apparatus and recording apparatus
US20090121418A1 (en) * 2007-11-08 2009-05-14 Ricoh Company, Ltd. Sheet feeding device and image forming apparatus
US20100014128A1 (en) * 2008-07-18 2010-01-21 Primax Electronics Ltd. Sheet-feeding scanning apparatus having mechanism for feeding business card
US20120049438A1 (en) * 2010-08-27 2012-03-01 Brother Kogyo Kabushiki Kaisha Sheet Feeding Apparatus Configuration for Roller Assembly
US20130043643A1 (en) * 2011-08-18 2013-02-21 Canon Kabushiki Kaisha Sheet feeding device and recording apparatus
US8695964B2 (en) 2010-08-20 2014-04-15 Brother Kogyo Kabushiki Kaisha Sheet conveying device
US20160109841A1 (en) * 2014-10-16 2016-04-21 Ricoh Company, Ltd. Sheet feeder and image forming apparatus incorporating the sheet feeder
US9563165B2 (en) * 2014-03-20 2017-02-07 Konica Minolta, Inc. Image forming apparatus

Families Citing this family (2)

* Cited by examiner, † Cited by third party
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JP4741988B2 (ja) * 2006-07-06 2011-08-10 キヤノン株式会社 シート材給送装置及び画像形成装置
CN114103151A (zh) * 2021-11-22 2022-03-01 铜陵四通环境科技有限公司 一种tdn高分子复合板成型用垫板、垫层铺装装置

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5253854A (en) * 1991-03-19 1993-10-19 Canon Kabushiki Kaisha Sheet feeding apparatus
JPH05270680A (ja) 1992-03-30 1993-10-19 Ricoh Co Ltd 給紙装置
US5358230A (en) * 1992-04-24 1994-10-25 Canon Kabushiki Kaisha Sheet supplying apparatus
US5372359A (en) * 1992-03-11 1994-12-13 Matsushita Electric Industrial Co., Ltd. Sheet feeding apparatus
US5725208A (en) * 1995-04-10 1998-03-10 Canon Kabushiki Kaisha Sheet supplying and conveying apparatus
US5984297A (en) * 1996-02-27 1999-11-16 Ricoh Company, Ltd. Compactly assembled sheet feeding apparatus with a movable paper tray and separating member
US5997198A (en) * 1996-10-22 1999-12-07 Seiko Epson Corporation Sheet feeder and printer
JP2000355429A (ja) 1999-06-18 2000-12-26 Sharp Corp 給紙装置

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5253854A (en) * 1991-03-19 1993-10-19 Canon Kabushiki Kaisha Sheet feeding apparatus
US5372359A (en) * 1992-03-11 1994-12-13 Matsushita Electric Industrial Co., Ltd. Sheet feeding apparatus
JPH05270680A (ja) 1992-03-30 1993-10-19 Ricoh Co Ltd 給紙装置
US5358230A (en) * 1992-04-24 1994-10-25 Canon Kabushiki Kaisha Sheet supplying apparatus
US5725208A (en) * 1995-04-10 1998-03-10 Canon Kabushiki Kaisha Sheet supplying and conveying apparatus
US5984297A (en) * 1996-02-27 1999-11-16 Ricoh Company, Ltd. Compactly assembled sheet feeding apparatus with a movable paper tray and separating member
US5997198A (en) * 1996-10-22 1999-12-07 Seiko Epson Corporation Sheet feeder and printer
JP2000355429A (ja) 1999-06-18 2000-12-26 Sharp Corp 給紙装置

Cited By (34)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020036377A1 (en) * 2000-08-08 2002-03-28 Ricoh Company, Ltd. Method and apparatus for image forming and effectively performing sheet feeding
US6824131B2 (en) * 2000-08-08 2004-11-30 Ricoh Company, Ltd. Method and apparatus for image forming and effectively performing sheet feeding using a sheet feed roller and a tilt member
US6616138B2 (en) * 2000-09-01 2003-09-09 Sharp Kabushiki Kaisha Recording device and a device for separating and feeding paper
US20030155702A1 (en) * 2002-02-08 2003-08-21 Toshifumi Togashi Method and apparatus for sheet feeding and image forming apparatus incorporating the same
US6948710B2 (en) * 2002-02-08 2005-09-27 Ricoh Company, Ltd. Method and apparatus for sheet feeding and image forming apparatus incorporating the same
US6862426B2 (en) * 2002-03-20 2005-03-01 Oki Data Corporation Sheet feeding mechanism and image forming apparatus
US20030179360A1 (en) * 2002-03-20 2003-09-25 Oki Data Corporation Sheet feeding mechanism and image forming apparatus
US20040201163A1 (en) * 2003-04-11 2004-10-14 Brock Kelly A. Media positioning at a picking location
US7029005B2 (en) * 2003-04-11 2006-04-18 Hewlett-Packard Development Company, L.P. Media positioning at a picking location
US20040251602A1 (en) * 2003-06-16 2004-12-16 Tom Ruhe Sheet media input structure
US7455288B2 (en) * 2003-06-16 2008-11-25 Hewlett-Packard Development Company, L.P. Sheet media input structure
US20080099976A1 (en) * 2004-08-24 2008-05-01 Seiko Epson Corporation Paper Feeding Method and Paper Feeder
US7597316B2 (en) * 2004-08-24 2009-10-06 Seiko Epson Corporation Paper feeding method and paper feeder
US20060082043A1 (en) * 2004-10-14 2006-04-20 Brother Kogyo Kabushiki Kaisha Paper feed unit, paper separating unit, and image forming apparatus
US7618036B2 (en) * 2004-10-14 2009-11-17 Brother Kogyo Kabushiki Kaisha Paper feed unit, paper separating unit, and image forming apparatus
US20060170147A1 (en) * 2005-02-03 2006-08-03 Canon Kabushiki Kaisha Sheet Feeding Apparatus, Image Reading Apparatus, and Image Forming Apparatus
US7384032B2 (en) * 2005-02-03 2008-06-10 Canon Kabushiki Kaisha Sheet feeding apparatus, image reading apparatus, and image forming apparatus
US20080093792A1 (en) * 2006-10-20 2008-04-24 Samsung Electronics Co., Ltd Sheet feeding unit and image forming apparatus having the same
US7673872B2 (en) * 2006-10-20 2010-03-09 Samsung Electronics Co. Ltd Sheet feeding unit and image forming apparatus having the same
US20080315497A1 (en) * 2007-06-20 2008-12-25 Seiko Epson Corporation Feeding apparatus and recording apparatus
US20090121418A1 (en) * 2007-11-08 2009-05-14 Ricoh Company, Ltd. Sheet feeding device and image forming apparatus
US8240657B2 (en) * 2007-11-08 2012-08-14 Ricoh Company, Ltd. Sheet feeding device and image forming apparatus
US7971866B2 (en) * 2008-07-18 2011-07-05 Primax Electronics Ltd. Sheet-feeding scanning apparatus having mechanism for feeding business card
US20100014128A1 (en) * 2008-07-18 2010-01-21 Primax Electronics Ltd. Sheet-feeding scanning apparatus having mechanism for feeding business card
US8695964B2 (en) 2010-08-20 2014-04-15 Brother Kogyo Kabushiki Kaisha Sheet conveying device
CN102381056B (zh) * 2010-08-27 2015-01-21 兄弟工业株式会社 片状物馈送设备
US20120049438A1 (en) * 2010-08-27 2012-03-01 Brother Kogyo Kabushiki Kaisha Sheet Feeding Apparatus Configuration for Roller Assembly
CN102381056A (zh) * 2010-08-27 2012-03-21 兄弟工业株式会社 片状物馈送设备
US8608158B2 (en) * 2010-08-27 2013-12-17 Brother Kogyo Kabushiki Kaisha Sheet feeding apparatus comprising a separation roller and a pad assembly
US20130043643A1 (en) * 2011-08-18 2013-02-21 Canon Kabushiki Kaisha Sheet feeding device and recording apparatus
US8899575B2 (en) * 2011-08-18 2014-12-02 Canon Kabushiki Kaisha Sheet feeding device and recording apparatus
US9563165B2 (en) * 2014-03-20 2017-02-07 Konica Minolta, Inc. Image forming apparatus
US20160109841A1 (en) * 2014-10-16 2016-04-21 Ricoh Company, Ltd. Sheet feeder and image forming apparatus incorporating the sheet feeder
US9523955B2 (en) * 2014-10-16 2016-12-20 Ricoh Company, Ltd. Sheet feeder and image forming apparatus incorporating the sheet feeder

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US20020060394A1 (en) 2002-05-23
JP2002068507A (ja) 2002-03-08

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